The change, the most dramatic shift in policy since Japan set up its post-war armed forces 60 years ago, will widen Japan's military options by ending the ban on exercising "collective self-defense", or aiding a friendly country under attack.

Abe's cabinet adopted a resolution outlining the shift, which also relaxes limits on activities in U.N.-led peace-keeping operations and "grey zone" incidents short of full-scale war, Defense Minister Itsunori Onodera told reporters.

Long constrained by the post-war constitution, Japan's armed forces will become more aligned with the militaries of other advanced nations in terms of its options. However, the government will be wary of putting boots on the ground in multilateral operations such as the 2003 U.S.-led invasion of Iraq.